Of the variety of fiber optic connectors in present commercial use is one manufactured and sold by the assignee hereof under the designation "SMA Fiber Optic Connector for Cabled Glass Fiber 905 Compatible". As is shown in FIG. 1, the components of this product, which is also known as a "fiber optic patch cord assembly", include a contact ferrule 10 having first and second end faces 10a and 10b at respective opposed ferrule ends, with a cable passage (not shown) extending through the ferrule and opening into end faces 10a and 10b. At end face 10a, a protective sleeve 12 is applied and a protective sleeve holder 14 is adapted to circumscribe sleeve 12. The further illustrated components include crimp sleeve 16 and protective heat-shrink tubing 18. As is seen in the partially-broken away depiction of ferrule 10 in FIG. 2, the ferrule has front shell 10c and back shell 10d.
In use of the apparatus of FIGS. 1 and 2, a fiber optic cable is prepared by first inserting an end thereof through heat-shrink tubing 18 and crimp sleeve 16, both of which have interior diameters exceeding the outer diameter of the fiber optic cable. Insertion of the cable, so assembled with the tubing and crimp sleeve, into the ferrule passage is prefaced by removing a length of the fiber outer jacket to expose a length of the fiber buffer tubing and then by removing a length of the exposed buffer tubing to expose a length of the optical fiber itself. The cable is inserted into the passage, following removal of protective sleeve holder 14, typically with rotation of the cable until the outer jacket bottoms against the ferrule and the fibrous matter collects on the knurled outer surface of back shell 10d. Crimp sleeve 16 is now advanced until the same circumscribes the bottomed and collected outer jacket of the cable. Sleeve 16 is now crimped upon the fibrous matter and the cable. Heat-shrink tubing 18, which will constitute a strain relief boot upon application of heat thereto, is now advanced over the crimped sleeve, following application of a suitable epoxy to the interior thereof and onto the cable jacket, and is heat-shrunk. The optical fiber is scribed as close as possible to end face 10a and gently pulled until it breaks and the fiber end face is suitably polished.
From applicants' perspective, while the described prior art product and practice have met commercial and technological needs in the fiber optic cable industry, the product is seen as not maximizing strain relief, particularly in that crimping force providing strain relief is limited to the expanse of the fiber jacket collected on the knurled ferrule surface. Further, the product and practice are seen as requiring excess components, particularly, the heat-shrink tubing and as being labor-intensive in requiring the heat application step.